31.08.2015 Views

AIR POLLUTION – MONITORING MODELLING AND HEALTH

air pollution – monitoring, modelling and health - Ademloos

air pollution – monitoring, modelling and health - Ademloos

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Analytical Model for Air Pollution in the Atmospheric Boundary Layer<br />

Analytical Model for Air Pollution in the Atmospheric Boundary Layer 17<br />

55<br />

Concluding, analytical solutions of equations are of fundamental importance in<br />

understanding and describing physical phenomena, since they might take into account<br />

all the parameters of a problem, and investigate their influence. Moreover, when using<br />

models, while they are rather sophisticated instruments that ultimately reflect the current<br />

state of knowledge on turbulent transport in the atmosphere, the results they provide are<br />

subject to a considerable margin of error. This is due to various factors, including in particular<br />

the uncertainty of the intrinsic variability of the atmosphere. Models, in fact, provide values<br />

expressed as an average, i.e., a mean value obtained by the repeated performance of many<br />

experiments, while the measured concentrations are a single value of the sample to which the<br />

ensemble average provided by models refer. This is a general characteristic of the theory of<br />

atmospheric turbulence and is a consequence of the statistical approach used in attempting<br />

to parametrise the chaotic character of the measured data. An analytical solution can be<br />

useful in evaluating the performances of numerical models (that solve numerically the<br />

advection-diffusion equation) that could compare their results, not only against experimental<br />

data but, in an easier way, with the solution itself in order to check numerical errors without<br />

the uncertainties presented above. Finally, the program of providing analytical solutions for<br />

realistic physical problems, leads us to future problems with different closure hypothesis<br />

considering full space-time dependence in the resulting dynamical equation, which we will<br />

also approach by the proposed methodology.<br />

6. Acknowledgements<br />

The authors thank to CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico)<br />

for the partial financial support of this work.<br />

7. References<br />

Abate, J. & Valkó, P.P. (2004). Multi-precision Laplace transform inversion. Int. J. for Num.<br />

Methods in Engineering, Vol. 60, page numbers (979-993).<br />

Adomian, G. (1984). A New Approach to Nonlinear Partial Differential Equations. J. Math.<br />

Anal. Appl., Vol. 102, page numbers (420-434).<br />

Adomian, G. (1988). A Review of the Decomposition Method in Applied Mathematics. J. Math.<br />

Anal. Appl., Vol. 135, page numbers (501-544) .<br />

Adomian, G. (1994). Solving Frontier Problems of Physics: The Decomposition Method, Kluwer,<br />

Boston, MA. .<br />

Blackadar, A.K. (1997). Turbulence and diffusion in the atmosphere: lectures in Environmental<br />

Sciences, Springer-Verlag.<br />

Bodmann, B.; Vilhena, M.T.; Ferreira, L.S. & Bardaji, J.B. (2010). An analytical solver for<br />

the multi-group two dimensional neutron-diffusion equation by integral transform<br />

techniques. Il Nuovo Cimento C, Vol. 33, page numbers (199-206).<br />

Boichenko, V.A.; Leonov, G.A. & Reitmann, V. (2005). NDimension theory for ordinary equations,<br />

Teubner, Stuttgart.<br />

Buske, D.; Vilhena, M.T.; Moreira, D.M. & Tirabassi, T. (2007a). An analytical solution of the<br />

advection-diffusion equation considering non-local turbulence closure. Environ. Fluid<br />

Mechanics, Vol. 7, page numbers (43-54).

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!